This invention relates to a novel support insulator for high-voltage high-power gas-insulated transmission lines, and more specifically relates to a novel generally triangular configuration for a support insulator which has improved dielectric properties and can be mechanically formed and assembled into a transmission line assembly.
In the novel insulator of the invention, the central bus is carried within the interior of a generally triangularly shaped insulator, and may be supported within a hub which is integrally formed with the triangular shape. The legs of the triangularly shaped insulator are generally inwardly bent toward the center of the triangle plane and the apices of the triangle engage the inner surface of the grounded support housing.
The triangle apices may be shaped to have a radius generally equal to that of the interior of the support housing. The exact shape of the generally triangularly formed arrangement is constructed to allow easy molding of the triangle form from high dielectric epoxy materials and the shapes further are designed to produce the most favorable dielectric stress distribution through the insulator.
The insulator design has improved electrical properties over designs of the conventional disk or conical insulator in that a long tracking distance is provided, and further the design uses less material than the conventional disk or conical insulator. Moreover, the insulator design permits fully open passages which allows the easy circulation of gas such as SF.sub.6 or the like through the housing interior. The design is also well adapted for use in flexible housings having a corrugated outer housing and inner conductor since the three engagement regions formed by the outer apices of the generally triangular shape will nest into the outer housing convolutions. If desired, the insulator can be split to permit the outer ends or insulator to be deformed out of a flat plane, thereby better enabling the insulator to nest within the convolutions of the outer housing.